how to Retrive the CLOB value from Oracle using java

After retrieving your data, you can use the getClob () method to return your Clob. Then you needs to open the Clob's stream to read the data (Mayb be char or binary data).

If the clob is known to be a plain string, you maybe also wish to use

clob.getSubString(1, (int) clob.length());

So try this

Clob clob = resultSet.getClob("DETAILED_DESCRIPTION")
record.add(clob.getSubString(1, (int) clob.length());

see http://www.java2s.com/Code/JavaAPI/java.sql/ResultSetgetClobintcolumnIndex.htm